Step 1: What you need
-A usb or ps2 2d-wheel mouse
- something to cut the plastic of the mouse with
Step 2: Cut up the mouse
Step 3: Assemble the mouse portion of the "tablet"
Step 4: Adding the pen/pencil grip
Tip: apply slight pressure to the mouse portion behind the ball with your finger if it doesn't work right.
In the future, i plan to make a version in a true pen-form out of an optical mouse.